404 Mr. E. C. Rimington on an Air- Core Transformer 



/3. 



Critical 

 values 



Values 

 of a for 

 I 



7- 



Max. 



values 



„ I 



Critical 

 phase- 



Phase- 

 angle for 

 I 





of «. 



max. — 

 -n 





ot iT 



angle. 



max. — . 

 -n 



10 



1-414= V2 



' 707 =^ 



2 



1-155 



O i 



144 44 



O ( 



125 16 



•9 



1-300 



•676 



1-920 



1-120 



142 26 



124 4 



•8 



1-210 



•650 



1-865 



1-090 



140 26 



123 2 



■7 



1-150 



•630 



1-825 



1-070 



139 



122 13 



•6 



1105 



•615 



1-795 



1050 



137 51 



121 36 



•5 



1070 



•605 



1-770 



1-032 



136 56 



121 11 



•4 



1045 



•595 



1-760 



1-020 



136 16 



120 45 



•3 



1-023 



•586 



1-750 



1-010 



135 39 



120 22 



•2 



1010 



•581 



1-740 



1-007 



135 17 



120 10 



•1 



1-002 



•578 



1-730 



1001 



135 4 



120 2 



It will be seen from the column of values for y that when 

 /S=l, or there is no magnetic leakage, the critical value of a 



is twice its value for maximum y- ; and the effect of leakage 



is to diminish this number, so that when /3 = 'l it is reduced 

 to 1*73. This is shown in the subjoined figure. 



B' 



Values of a.. 



The curve OCB represents the critical part of the curve 

 III (Plate X.) when there is no leakage, and A comes midway 

 between and B, so that OA=-JOB; also 06=^2 = 1-414, 

 OA='707,and, if the point represent 100 divisions, AC = 15 J 

 divisions. 



The curve OC'B' represents the critical part when /3 = 'l; 

 OB r = 1-002 and 0^= '578 = *5770B / ; also A'C = -12 

 division. Hence we see that the effect of magnetic leakage 



